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FTFC20 Bellanca Aircruiser C-27A by Matagami Designs

...willsonman has pointed it out that it should probably have a little more roll authority.
I know you want to keep your model as scale as possible, but the most efficient method to add roll authority is moving your ailerons as far as possible from the center.

1 square inch of ailerons at the wing tip is twice as effective as the same square inch at mid-wing.
 

willsonman

Builder Extraordinare
Mentor
Pretty sure this is understood however, when making a scale model there are sometimes compromises that the designer is not willing to make. At some point you deviate so far from scale that you are in the territory of "Sport-Scale" where you've gone so far to make that airplane fly in a way that is NOT scale. A perfect example is the FT Master Series Corsair. While it looks like a Corsair, no question, it has no tendency to fly like the real one. This is where reading up on the history of an aircraft is hugely in play. I suspect with a name like "Aircruiser" it was not intended to be aerobatic at all. It was meant to "cruise" and be a stable platform for transport.

Having flown this model again on Saturday (another great flight), The rudder authority is so good on this airplane. It leads me to believe this is the case. Roll control was more to keep the wings level and coordinating the turn with the rudder was the intended technique. This is a far cry from the beginner tactic of "bank and yank."

As with any design, the designer is at liberty to incorporate design to capture the look and flight characteristic of each subject. As-built, this airplane is controllable, but there is a lacking for control under extreme conditions. There is AMPLE power, and of note is that it is far more powerful than the full-size. These are checks and balances. They get ironed out with time and compromise.
 
Thanks @FoamyDM.

Here is the video from yesterdays flight. It is definitely a very forgiving bird now that its mostly dialed in. A big difference compared to my Maiden flight experience.


Also here is a picture for the swappable gear/float. I didn't have enough time to finish yesterday so i didn't get to test. I'm not sure how the extra drag below the CG will effect the flight characteristics? i just need to reinforce the skewer holes on the floats and it should be ready to test.

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Also going back to the roll authority i would indeed like to see it do a barrel roll or an immelmann turn @Sheriff :D

I guess i will consider growing the Control surfaces out 2" on each end this way they are still fairly protected from landing on a wing tip or something and will help a bit with roll authority. Its not too much of a deviation from the scale look and i think the idea of sport scale just seems fun. I definitely enjoy watching it cruise the skies as well though. :cool:
 

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Thanks @FoamyDM.
I'm not sure how the extra drag below the CG will effect the flight characteristics?
The main issue with floats is the most lateral surface will now be in front of the plane, making it unstable, like a shuttlecock flying backwards.

That's why most landplane converted to floatplane have additionnal tail surfaces. The Aircruiser did too:
 

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Here is a clip of the Bellanca flying with pontoons attached.


I had nearly ripped the wheel struts off the previous day trying to get it trimmed and flying straight so once i had everything glued back i took it to a larger field. It still wanted to fly left but i eventually got it trimmed in to be controllable.

I also enlarged the aileron control surfaces since i noticed in pictures that they were quite a bit larger on the actual plane. It seems that when transferring to CAD i had messed this up. :oops:

I have been contemplating smoothing out the wings for V2 and giving it a master series style or speedwing but not sure if there is a good way to prevent tip stalls other than the typical under cambered wing design of a FT model or any other considerations for this.

Let me know your thoughts.

RAD.jpg
 
Well done !!

Your aircraft seems way out of trim at first. Maybe you should throw it a few times without power over long grass to see if it glides straight before commiting to your first flight.

Insight is 20/20 ;-)
 
I have been contemplating smoothing out the wings for V2 and giving it a master series style or speedwing but not sure if there is a good way to prevent tip stalls other than the typical under cambered wing design of a FT model or any other considerations for this.
May I suggest you keep the wing as is but mount the floats with a rubber band to prevent ripping off the wheel struts.
 
May I suggest you keep the wing as is but mount the floats with a rubber band to prevent ripping off the wheel struts.
I want to have a basic version which is easy to build (V1.5) and then a master series style version with more advanced techniques(V2). I love the look of the V1.5 because it fits well with the FT style and flies really nice but I feel the wing, nose, and struts could be slightly improved for a more scale looking V2.:unsure:

I told @willsonman that i wished i would have put rubber bands on the floats the other day. I think this could have been easily done i'm just not a fan of the way it looks. :D
 
So i have the V2 wing modeled up and have a few questions.

The airfoil shape is the same as before but i have extended the bottom plate to the TE and added chamfers similar to a nnspeedwing.
Do i need to add a second smaller spar before the control surfaces about where the C-fold was before?

wing cross section.PNG

For the wing tips I have the bottom plate start to angle up and then fold over at the very end. I feel this model has a pretty low stall speed; however i am curious if this will this reduce the AOA on the wing tip and help prevent tip stalls? I am not sure if there is a better way to do this since i don't want to try twisting the wings for washout?

wing tip.PNG
Thanks!
 

rockyboy

Skill Collector
Mentor
IMHO, I don't think there is a need for a second spar back by the control surface - the edge of the two foam pieces glued together, even when feathered down to make a nice smooth angle, will be plenty strong for the control surface.

As for closing off the wing tip, designing in an upward sweeping angle will be more stable than having the bottom flat all the way out - but both of these will be less stable than leaving the tips under-cambered. How this plays out on the model is something you'll need to test out, and adjust to your taste as a pilot. You might be perfectly fine with the lower drag, higher speed, and less stability at low speeds of covering in the tip. Or if might feel too unstable and prone to taking a downward spin on low speed turns (like setting up for a landing - I lost several Cadron 460 prototypes's to this).
 
Slowly working out the kinks in the V2 plans. Got all the fuse pieces and tail feathers made.

20191029_230344.jpg

I have decided I'm going to spray paint rather than use monkote covering since I wasnt having too much luck with it. o_O Maybe I will try it again on a smaller build. Decided to try a center hinge for the rudder and elevator after reading some posts by @PoorManRC. Seems to be working well. (y)

Now to give it wings. :D